Venus information for kids

Venus is called Earth's twin sister, but it is Earth's twin in size only. Journey to Venus and learn about why life can't exist on the brightest planet in the solar system.

Photo Credit: NASA

By Donald Powell
Venus is the second planet from the sun and lies between Mercury and Earth. It is the brightest of all planets and is named after the Roman goddess of love and beauty. Long considered Earth's twin sister, Venus resembles Earth in size, shape and mass, but differs from Earth in all other aspects. In reality, Venus is one of the most inhospitable places in the solar system. Most of what we know about Venus comes from data collected by space probes.

Venus shares many similarities to Earth. Its mass is 82% of Earth's mass (at 4.87 x 10^24 kilograms), its density is 89% of Earth's density (at 5.243 kilograms per meter cubed), and its diameter is 95% of Earth's diameter (at 7,545 miles). Venus is separated from Earth by 25 million miles and from the sun by 68 million miles. Like Earth, Venus suffers from the Greenhouse Effect, but the similarities end here.

The length of one day is 117 Earth days. It takes Venus 225 days to complete one orbit of the sun, and Venus rotates from east to west slowly on its axis, completing one rotation every 243 days. Unlike Earth, Venus has no moons and no magnetic field because of its slow rotation.

There is no life on Venus because it is hot and dry. The dense cloud cover prevents anyone from seeing much of the planet's surface. However, once you penetrate the cloud cover, you'll find the planet to be quite poisonous. The temperature is the hottest in the solar system, reaching as high as 900 degrees Fahrenheit (482 degrees Celsius). The reason why the planet is so hot is due to the Greenhouse Effect. Carbon dioxide, nitrogen, water vapor, acids, and heavy metals make up the atmosphere of Venus. The clouds contain sulfur dioxide. When the sunlight warms the planet, heat is trapped on the planet's surface by the carbon dioxide in the atmosphere. No heat radiates out from the planet. When the surface of the planet is heated, more carbon dioxide is released. It is this Greenhouse Effect that makes Venus so unfriendly.

The surface of Venus is rocky and consists of volcanoes, channels, mountains, and many craters. The volcanoes on Venus are still active, and spouting mounds of lava can be seen from photographs returned by space probes. Spidery geologic formations called arachnoids line the surface of Venus. Two continents have been photographed by space probes on Venus. Ishtar Terra is located in the Northern Hemisphere and is about the size of Australia. This continent is named after the Babylonian Goddess of Love. The other continent is located near the equator and is called Aphrodite Terra. Scientists have deduced that the planet's surface is relatively young. Based on data received from the Magellan probe, it is possible that a lava eruption covered the planet 300 to 500 years ago, destroying any signs of life in the process.

Although Galileo first observed the planet in the 1600s, most of what we know about Venus comes from space missions in the late twentieth century. The Russians launched the Venera 9 in 1961 to get initial photographs of the planet. The Americans then launched the Mariner 2 in 1962 to also get data about the planet. Both the Venera 9 and the Mariner 2 were lost in orbit. The first atmospheric probe was launched by the Russians in 1965, but these probes did not get very far into the planet before crashing into Venus. Probes were finally able to approach the planet in the mid to late 1970s and images of the planet were obtained in subsequent missions. Eventually, detailed maps were created using synthetic apertar radar on the space probe Magellan from 1990 to 1994.

More missions may be planned in the future to obtain additional data about the planet's surface. Some European missions are scheduled in 2005 to obtain detailed information about the atmosphere and to map the orbit of Venus. These missions may give us an idea as to the fate of the planet, and what may be in store for Earth in the future.